Product category:
Materials Testing
News Release from: Metrohm UK | Subject: 743 Rancimat
Edited by the Manufacturingtalk Editorial
Team on 07 August 2006
Determination of the oxidation stability
index
Fats are an important component of our diet because they contain essential substances as polyunsaturated fatty acids.
Fats are an important component of our diet because they contain essential substances as polyunsaturated fatty acids Fats are also necessary for absorbing the essential fat-soluble vitamins (A, D, E and K) which are beneficial for our health
This article was originally published on Manufacturingtalk on 13 Jun 2007 at 8.00am (UK)
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Oxidative stability of diesel and biodiesel
The 873, based on the 743 Rancimat from Metrohm UK, is specifically designed to analyse the oxidative stability of biodiesel, diesel and blends.
Evaluating effects of antioxidants on edible oils
Oxidative stability is an important criterion for evaluating the quality of oils, fats and fatty acid methylesters (biodiesel).
Therefore at least a minimal intake of fat is necessary.
Providing 9 kcal of energy per gram, fats are a very concentrated source of energy for the human body.
Fat is primarily found in meat and dairy products but also in plants (e.g seeds, soybeans, olives, nuts).
Further reading
Determination of oxidation stability of Biodiesel
The Metrohm 743 Rancimat is a modern, PC-controlled analytical instrument for the comfortable determination of the oxidation stability of Biodiesel (fatty acid methyl esters, FAME).
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The 743 Rancimat, from Metrohm allows simultaneous and rapid Oil Stability Indexes (OSI) to be performed.
Effectiveness Of Anti Oxidants In Food Materials
Metrohm's new 743 Rancimat uses the technique of thermal oxidations on fats and edible oils.
Most foods contain some fat.
The main components of a basic unit of fat are three fatty acids individually bound to glycerol.
* Especially animal fats and food containing animal fats (e.g lard, butter, meat sausages) as well as fats from tropical plants (coconut fat, palm fat) are rich in saturated fatty acids.
Whereas saturated fatty acids do not posses any carbon-carbon double bonds, monounsaturated fatty acids do have one.
Examples of vegetable oils rich in monounsaturated fatty acids are olive oil, rape oil and peanut oil.
These also contain high amounts of oleic acid.
When there is more than one carbon-carbon double bond present in a fatty acid then it is polyunsaturated.
Most vegetables contain polyunsaturated fatty acids.
Examples of oils rich in polyunsaturated fatty acids are safflower oil, sunflower oil, soybean oil, corn oil and cottonseed oil.
Fish also contain large amounts of unsaturated fatty acids.
Metrohm has a variety of proven methods and instrumentation for the determination of the quality of fats and oils at hand.
Find some examples here: The oxidative stability of fats determined with Metrohm's 743 Rancimat Fatty acids and antioxidants Natural fats are mixed triglycerides of mostly saturated and some unsaturated fatty acids.
Common vegetable and animal fats are coconut fat, palm fat, margarine and butter.
Oxygen can oxidize fatty acids in a multi-step reaction that occurs in principle according to a radical chain mechanism.
The oxidation products formed by this reaction (mainly formic acid) are volatile.
Antioxidants prevent the degradation of oxidation-sensitive vitamins, amino acids and unsaturated fatty acids.
Determination of the oxidative stability The determination of the oxidative stability of natural fats is a standard quality control method in the food industry.
Metrohm's 743 Rancimat offers an easy and fast method to determine the oxidation stability index (OSI) of natural fats.
The Rancimat Method is considerably less costly, less labour-intensive but as accurate as the traditional active oxygen method (AOM).
Air is blown through the heated and thermostatted sample (50_220 C) in order to oxidize it.
The stream of air then carries over the volatile oxidation products (normally formed at the end of the oxidation process) to a measuring vessel containing deionized water.
The readings of the conductivity measurement can be plotted as a function of the time required for the oxidation.
The inflection point of this oxidation curve is known as the induction time which serves as a measure of quality of the fat tested.
Product information The 743 Rancimat is an instrument with two separate heating blocks.
The temperature of each block, containing four disposable sample vessels, can be controlled separately.
This setup allows the easy and time saving analysis of several different oils simultaneously.
In addition the 743 Rancimat allows predicting the shelf lives of natural oils and fats.
The oxidative stability of oils determined with Metrohm's 743 Rancimat Fatty acids and antioxidants Natural oils are normally mixed triglycerides of saturated and unsaturated fatty acids.
Common edible vegetable oils are olive, soybean, peanut, sesame, cottonseed, rapeseed, poppy seed and linseed oil.
Oxygen can oxidize fatty acids in a multi-step reaction that occurs in principle according to a radical chain mechanism.
The oxidation products formed by this reaction (mainly formic acid) are volatile.
Antioxidants prevent the degradation of oxidation-sensitive vitamins, amino acids and unsaturated fatty acids.
Determination of the oxidative stability The determination of the oxidative stability of natural oils is a standard quality control method in the food industry.
Metrohm's 743 Rancimat offers an easy and fast method to determine the oxidative stability index (OSI) of natural oils.
The Rancimat Method is considerably less costly, less labour-intensive but as accurate as the traditional active oxygen method (AOM).
Air is blown through the heated and thermostatted sample (50_220 C) in order to oxidize it.
The stream of air then carries over the volatile oxidation products (normally formed at the end of the oxidation process) to a measuring vessel containing deionized water.
The readings of the conductivity measurement can be plotted as a function of the time required for the oxidation.
The inflection point of this oxidation curve is known as the induction time which serves as a measure of quality of the oil tested.
The 743 Rancimat is an instrument with two separate heating blocks.
The temperature of each block, containing four disposable sample vessels, can be controlled separately.
This setup allows the easy and time saving analysis of several different oils simultaneously.
In addition the 743 Rancimat allows predicting the shelf lives of natural oils and fats. Request a free brochure from Metrohm UK ...
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